Can we create an ABAP program without using Y or Z?
No, this is because all non Yor Z programs are standard SAP programs.

1. How data is stored in cluster table? 
Each field of cluster table behaves as tables which contains the no. of entries. 

2. What are client dependant objects in abap/sap? 
SAP Script layout, text element, and some DDIC objects. 

3. On which even we can validate the input fields in module progams? 
In PAI (Write field statement on field you want to validate, if you want to validate group of fields put in chain and End chain statement.) 

4. In selection screen I have three fields, plant mat no and material group. If I input plant how do I get the mat no and material group based on plant dynamically? 
AT SELECTION-SCREEN ON VALUE-REQUEST FOR MATERIAL. 
CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST' to get material and material group for the plant. 

5. How do you get output from IDOC? 
Data in IDOc is stored in segments, the output from Idoc is obtained by reading the data stored in its respective segments. 

6. When top of the page event is triggered? 
After excuteing first write statement in start-of-selection event. 

7. Can we create field without data element and how? 
In SE11 one option is available above the fields strip. Data element/ direct type. 

8. How do we debug sapscript? 
Go to SE71 give lay set name , go to utilities select debugger mode on.

9. Which transaction code can I used to analyze the performance of ABAP program. 
TCode AL21.

10. How can I copy a standard table to make my own z_table.
Go to transaction SE11. Then there is one option to copy table. Press that button.  Enter the name of the standard table and in the Target table enter Z table name and press enter.

Following are some of the answers which I gave upto my knowledge.

1. What is the use of 'outerjoin' 
Ans. With the use of outer join you can join the tables even there is no entry in all the tables used in the view.
        In case of inner join there should be an entry in al the tables use in the view.

2. When to  use logical database?
Ans. Advantage of Logical databases:
        less coding s required to retrieve data compared to normal internel tables.
        Tables used LDB are in hierarchial structure.

3. What is the use of 'table index'?
Ans .Index is used for faster access of data base tables.

4. What is the use of 'FOR ALL ENTRIES'?
Ans. To avoid nested select statements we use SELECT FOR ALL ENTRIES statement.
        If there r more than 10000 records SELECT FOR ALL ENTRIES is used.
        Performance wise SELECT FOR ALL ENTRIES is better to use.

5. Can you set up background processing using CALL TRANSACTION?
       Yes,Using No Screen Mode.

6. What are table buffers?
    Table buffers reside locally on each application server in the system. The data of buffered tables can thus be accessed 
    directly  from the buffer of the application server. This avoids the time-consuming process of accessing the database.

    Buffering is useful if table needs to be accessed more no. of times in a program.

With Compliments from: Pavan

1. How do I set a flag for a field in any table?
Create a char field of length 1. for example field STAS-LKENZ is Deletion Indicator. It means that if the value in the field is 'X' then that record has been deleted.

2. Can I execute user exits? If yes, how?
Yes you can. after finding the user exit, you need to use, goto CMOD add ur user-exit to your project. Then activate the FM which you require. Now go into that function module there will be a Include program wit name ZX* . Double click on it, it will ask to create an object, answer it Yes and then write your code in it. 

3. How do I find the output type of a table or a program?
Table TNAPR / NAST               *-- Raj

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